Computing-machine.



No. 757,508. PATBNTBD APR.19, 1904'. J. A. SCOTT A. W. P. TAYLOR.

COMPUTING MACHINE.

APPLIUATION FILED PEB. 24. 190s.

H0 MODEL.

- Z5/venan J MxSYCOZ- UNITED STATES Patented April I9, 1904.

PATENT CEEICE.

JAMES A. SCOTT AND WILLIAM E; TAYLOR, OF CHICAGO, ILLINOIS.

COMPUTING-MACHINE.

SPECIFICATION forming pare of Lettere Patent No. 757,508, dated April 1o, '1964.

l Application filed February 24, 1903. Serial No. 144,684. (No model.)

To @ZZ whom it may concern:

Be it known that we, JAMES A. SCOTT and WILLIAM F. TAYLOR, citizens of the United States, residing in the city of Chicago, county of Cook,` and State of Illinois, have invented a new and useful Improvement in Computing- Machines, of which the following is a specilication.

Our invention vrelates to computing-machines embodying one or more numerical tables; and the objects of the invention are, first, to provide means whereby at any one time a portion only of said table or tables is exhibited or in sight, and, second, to provide convenient and expeditious means forexhibiting or bringing into sight Vthe required result-number. We attain these objects by the mechanism illustrated in the accompanying` drawings, in which- Figure l is a plan view of the device. Fig. 2 is a sectional view thereof, taken on the line 2 2 of Fig. l. Fig. 3 is a fragmentary view showing the method of supporting the outer disk, also the click or spring-detent operative thereon. Fig. 4 is a fragmentary view showingr said click in plan, and Fig. 5 is a fragmentary view showing a portion of the rim of the outer screen at the point beneath the sight where said rim is cut away for exhibiting the figures on the outer number-disk.

Similar reference characters denote similar parts throughout theseveral views.

The axle a is rigidly secured within the casing b by means of the set-screw a', screwing in the boss b in the bottom of said casing, or said axle may be secured in any other suitable manner. Itis desirable that said axle be considerably inclined from the vertical in order that the number-disks e d may be correspondingly inclined from the horizontal, to thereby facilitate the manipulation of the device. Said casing Consists of a box or housingv for the rest of the mechanism and is preferably circular in outline.

Near its upper portion the axle a is provided with a fixed collar a2, which, in conjunction with said axle, forms a pivot-bearing for said revoluble disk c. The hub c on said disk operates to steady the same and cause it to lie at all times in a plane at right angles to said dev ice are one hundred in number.

axle ct. Said hub also acts as distance-piece to hold the inner screen e at'the proper height above the4 inner number-disk c above mentioned. Said number-disk has on its face two series of numbers arranged in concentric circles o2 and c3. I There are one hundred numbers in said'outer number-circle running from l to 100 and progressing, preferably, in an anticlockwise direction, so that when said disk is rotated in a clockwise direction, which ordinarily is most convenient for the operator, the numbers passing any given point will be ascending in value, it being usually more convenient to read on an ascending scale than ona descending scale. On the inner numberscale c3 there are also one hundred numbers which in the present device represent the product obtained by multiplying the corresponding number in the outer circle c2 by a given multiplier. Our mechanism is well adapted for use in an assessors office for computing taxes, and to facilitate explanation an example of the use of the mechanism in this connection will be described. The numbers running from one to one hundred (1 to 100) in the outer circle c2 represent the valuations, and the numbers in the inner circle c3 represent the assessment obtained by using the tax rate as a multiplier. For instance, if the tax rate is one dollar and twenty-five cents per hundred dollars the number in the inner circle adjacent to the number 100 of the outer circle will be $1.25, while the number in the inner circle adjacent to the number 50 of the outer circle will be "$0.625.

The disk c has preferably upon its periphery a set of serrations f, which in the present These serrations are engaged by the click g, which is here shown to consist o f a headv g', mountedV upon the flat steel spring g2, said spring being fixed -to one of the legs t/of the outer'screen la. The parts are so related and constructed vthat said click will yieldy and permit the disk c to be rotated to the desired point by hand;

but when said point is reached the stiffness g of the click and the serrations fof the disk IOO are aecuratel y formed, so as to prevent backited at a time, thus avoiding' doubt on the part or' the operator as to what number is to be read oil". Y

The screen e above mentioned lies above the disk c and consists oi' the disk portion e and the extension which latter iorms the sight. Said disk portion is secured to the top of the axle a by means of the washer @3, but may be held rigid in any other suitable manner. By preference the sightis also secured to the casing I) by means of the screws e". The diameter of the disk portion e' oi' the screen e is great enough to cover the inner numbercircle c and hide the numbers thereof Yfrom view without covering the outer numbercircle c2.

rlhe outer number-disk cl bears upon its surface the outer numbercircle d and inner number-circle d2, which correspond, respectively, to the number-circles e2 and c3 ot' the disk c. On said disk (Z, however, the numbers on the outer circle progress by hundreds and run from 100 to 10,000. The numbers oi' the inner circle are the products obtained by multiplyingr the outer numbers by the given multiplier, or in a tax-computing machine the numbers of the outer circle represent the valuation and the numbers of the inner circle represent the assessment. The disk d also has preferably upon its periphery a series oi' seri-ations e', engaged by the click j in a manner similar to and for the same purpose as the serrations f are engaged by the click g. Said click j is mounted by prefererence upon the casing Said disk (Z is revolubly supported by means of rollers 7c, mounted upon suitable xed brackets le'. In order .to retain said disk in position upon said rollers, a track is formed upon said disk, the preferred construction being' here shown in which two concentric flanges 'la m are formed upon the under side of said disk in such a manner as to eng'age said rollers 71:, but prevent eccentric motion of said disk. rlhis construction has the advantage that the disk may be simply lifted from its place when the screen /t is removed. y

Both the inner and outer disks c and Z are provided with a series of pockets or apertures n a, adapted to partially receive the point of a lead-pencil, so that the operator may readily rotate the disks to the proper position with the means in hand.

The disk CZ is annular in the present machine-that is to say, the central portion thereet' is removed to admit the legs lt', whereon the screen 71, is mounted, as above mentioned.

Said screen 7L is so constructed as to cover all l ot' the inner number-circle rl on the disk rl, except at the sight e2, at which point said screen is cut away, as best shown in Fig. 5.

To illustrate the operation oi'l the device, let it be supposed that it is to be used tor computing taxes and that the tables or numbercircles Z2 and c are calculated on a tax-rate or multiplier oi' one dollar and twenty-live cents per hundred dollars valuation, and let it be further supposed that it is required to lind the assessment on a valuation oi two thousand four hundred and thirty-live dollars. lhe outer disk is rotated by the operator until the number exhibited on the outer number-circle (Z through the sight @e is 2,400. '.lhe number on the inner number-circle fl on disk Il will be $30.00. By reason oi the click y' the disk (Z will then remain in the position thus reached. The operator next rotates the inner number-disk e until the number 235 is exhibited on the outer number-circle d through the sight e2. The number consequently exhibited on the inner number-circle e through said sight will be 50.4375 or forty-three cents seven and one-half mills, which is the assessment on thirty-live dollars. The operator now has $30 and t0/e375 exhibited on the two inner number-circles e and d. These amounts are then added together and the complete assessment is 'found to be 80.4375, or. in round numhers,thirty dollars and forty-four cents.

lt will be, of course, understood that this machine is best adapted .tor use under conditions in which the same multiplier or rateiiactor is employed for a series of computations. For this reason the machine is particularly7 suited for computing assessments, because the tax rate remains the same for all the computations in any given district at any single levy.

We propose to provide substitute numberdisks to permit the selection of disks in which the product numbers are computed on therequired basis or rate.

It is evident that, ii' desirable, the numbercircles may be printed on sheets oi' paper or other light material and pasted or otherwise fastened upon the surfaces of the disks. Moreover, it is not essential that the products or assessment-circles have a smaller diameter than the multiplicand or valuation circles.

By properly shifting the decimal-point in reading the results the machine may be used for numbers either greater or less in value than the numbers appearing on the disks.

Vhat we claim as new, and desire to secure by Letters Patent, is-

l. In a eomputing-machine, the combination or' an annular number-disk, the central portion whereoil is removed; a plurality olf number-circles on said number-disk; a screen above said disk covering one of the series of numbers on said number-disk, and legs for supporting said screen, said legs passing through the central aperture of said number-disk.

2. In a computing-machine, the combination of a rotating number-disk having number-circles thereon, a screen for covering one of the number-circles on said disk, rollers for supporting said number-disk, and a track on said number-disk for engagement with said roller to prevent eccentric rotation of said number-disk.

3. In a computing-machine, the combination of two independently-movable numberdisks, each of said disks bearing upon their surface two series ot' numbers, one series on each of said disks representing.multiplicand and the other series representing products, and the numbers in one multiplicand series progressing by units from one to one hundred and the numbers in the other multiplicand series progressing by hundreds from one hundred upward.

4. In a computing-machine, the combination of an annular number-disk, the central portion whereof is removed; a plurality of number-circles on said number-disk, and a ring concentric with said number-disk constituting a stationary screen, said screen being supported above said number-disk and the outer diameter of said screen being suiiciently great to cover one of said number-circles.

5. In a computing-machine, the combination of two rotatable number-disks, each bearing a plurality of number-circles thereon, a pivot for centrally supporting the inner one of said number-disks, and rollers for supporting the outer one of said number-disks.

6. In a computing-machine, the combination of two independently-movable numberdisks, each of said disks bearing upon their surface two series of numbers, one series on each of said disks representing multiplicands and the other series representing products; and the numbers in one multiplicand series progressing by a common difference equal to the difference between the highest and lowest numbers in the other multiplicand series.

7 In a computing-machine, the combination of two independently-movable numberdisks, each of said disks bearing upon their surface two series of numbers, one series on each of said disks representing multiplicands and the other series representing products; and a sight for exhibiting one at a time the numbers in the multiplicand series.

8. In a computing-machine, the combination of an annular number-disk, the central portion whereof is removed; a plurality of number-circles on said disk; a screen above said disk covering one of the series of numbers thereon; legs passing through the central aperture of said number-disk for supporting said screen; a second rotating number-disk having the same axis of rotation as said annular number-disk; a plurality of number-circles on said second number-disk; a screen above said second disk for covering one of the series of numbers thereon; and pockets in each of said disks for receiving a pencil or other implement for rotating said disks.

JAMES A. SCOTT. WILLIAM F. TAYLOR.

Witnesses: l

LoUIs B. ANDERSON, CHARLES J. JONES. 

